--  @testpoint:opengauss关键字catalog(非保留)，作为函数名
--关键字不带引号-成功
drop function if exists catalog;
create function catalog(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--清理环境
drop function catalog;

--关键字带双引号-成功
drop function if exists "catalog";
create function "catalog"(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--清理环境
drop function "catalog";

--关键字带单引号-合理报错
drop function if exists 'catalog';
create function 'catalog'(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/

--关键字带反引号-合理报错
drop function if exists `catalog`;
create function `catalog`(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/